JPH05119479A - Resist method for resist coating - Google Patents

Abstract

PURPOSE:To enable high accuracy exposure corresponding to fine patterns formed in a exposure mask by increasing the adhesion property of a resist layer and the mask. CONSTITUTION:A first resist 2 is applied on a resist substrate 1 having high flatness accuracy and the whole surface of the resist 2 is exposed to light, on which a second resist 3 is applied. A ferrite block bar 5 is fixed to the second resist 3, and then the resist layers are developed so that only the first resist 2 exposed is dissolved in the developer while the second resist 3 remains on the ferrite block bar 5 to form a resist layer of high flatness accuracy. Therefore, by maintaining high flatness accuracy of the resist substrate 1 to be coated with resists, the first and second resists 2, 3 applied on the substrate 1 have higher flatness accuracy. Since the work is fixed on the second resist 3 and only the exposed first resist 2 is dissolved in the developer, the resist layer of high flatness accuracy can be formed on the upper surface of the work made in one wafer-like body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resist coating technique in photolithography, and more particularly to a resist coating method suitable for manufacturing a magnetic head slider for a fixed magnetic disk device.

[0002]

2. Description of the Related Art In recent years, a two-rail monolithic floating magnetic head slider has been devised to increase the recording area of a magnetic disk. As shown in FIG. 7, such a magnetic head slider is composed of a slider body S and a U-shaped yoke portion Y, and a predetermined sliding surface (5a) with a recording medium extends in the sliding direction. The air bearing portions (9) and (9) having heights parallel to each other are provided, and the track portion (50) is formed on the winding hole H side of the air bearing portion (9).

The method of manufacturing the above magnetic head slider is
For example, it is disclosed in Japanese Patent Application Laid-Open No. 1-315021, and a method of forming the air bearing portion 9 and the track portion 50 in this case will be described with reference to FIGS. 8 to 13. As shown in FIG. 8, two large and small ferrite blocks (51) and (52) having winding grooves (54) and (55) for the winding hole H are integrated through a gap member (53) to form a block bar (5 ) Is formed. The disk sliding surface (5a) of the block bar (5) is polished so that the distance between the track portion and the winding hole H, which will be described later, that is, the depth length D becomes a predetermined length. Next, as shown in FIG. 9, a resist (31) is applied to the disk sliding surface (5a), and an original plate having a predetermined pattern (not shown) is applied.
The resist (31) is exposed to ultraviolet light through a mask (hereinafter referred to as a mask) and further developed, so that the air is formed on the disk sliding surface (5a) of the block bar (5) as shown in FIG. Resist pattern corresponding to bearing and track
(32) is formed. Only the ferrite surface exposed on the disk sliding surface (5a) is chemically etched to a predetermined depth.
As shown in, the air bearing parts (9) (9) and the track part (5
0) is formed.

Furthermore, a track portion (5
(0) Adjacent to (0)
An IG two-rail monolithic magnetic head slider has also been proposed. In this case, since the metal magnetic material in the vicinity of the gap is eroded by the above chemical etching and the track portion cannot be formed, the tape sliding surface of the block bar (5) can be formed by a dry etching method such as ion beam etching. Remove unnecessary parts of (5a),
The (50) must be formed.

However, in the dry etching method such as the ion beam etching, the resist has to be applied thicker than the chemical etching, and the thickness is required to be about twice the etching amount. However, no specific method has been proposed for such a thick coating method.

Conventional resist coating methods include coating by pulling up from the resist layer, coating by pouring, coating by a roller, coating by a spray, and coating by a spinner. In all cases other than coating by a spinner, control of the resist thickness is performed. And the adhesion to the mask is poor, and it is difficult to form a track portion having a fine width with high accuracy.

The coating of resist by a spinner is the only coating method that makes it easy to control the resist thickness.
When applied to the formation of the air bearing portions (9) (9) and the track portion (50) of the two-rail monolithic type magnetic head slider, there are the following problems. Block bar mentioned above
In order to form the air bearing part (9) and the track part (50) by (5) for a plurality of block bars at one time in order to improve productivity, as shown in FIG. After the block bar (5) is integrated into a wafer, a resist (31) is spinner coated as shown in FIG.

At this time, due to an error in the thickness of the block bar group and an uneven thickness of the adhesive for joining the block bar group to the substrate (4), a step or a gap is generated in the block bar group, and the block bar group is coated on the upper surface of the block group. The resist (23) has irregularities,
As shown in FIG. 13, the adhesiveness with the mask (8) is deteriorated and the accuracy of the resist pattern is low. Therefore, there is a problem in that the width of the track portion after etching varies and the yield is greatly reduced.

[0009]

The present invention clarifies a resist coating method capable of greatly improving the accuracy of a resist pattern by eliminating the unevenness of the resist coated on the upper surface of a work such as a block bar, This is to solve the above problem.

[0010]

According to the resist coating method of the present invention, a first resist (2) is coated on a resist substrate (1) having a high flatness accuracy, and the entire surface of the resist is exposed to form a fine pattern. The required second resist (3) is replaced with the first resist (2)
A work such as a ferrite block bar (5) for applying a fine pattern on the second resist (3) is fixed onto the second resist (3) and then developed to develop a first resist (2) previously exposed. ) Is dissolved in the developer, and the second
Only the resist (3) is left to form a resist layer (3a) having high plane accuracy.

[0011]

[Operation and effect] If the plane precision of the resist coating surface of the resist substrate (1) is increased, the plane precision of the first and second resists (2) and (3) coated on the substrate is also enhanced.

Furthermore, since the work is fixed on the second resist (3) and only the exposed first resist (2) is dissolved in the developing solution, the upper surface of the work is a resist layer (3) having a high plane accuracy.
a) can be formed, the degree of adhesion between the resist layer (3a) and the exposure mask (8) is increased, and highly accurate exposure can be performed corresponding to the fine pattern formed on the mask.

Therefore, a resist pattern faithful to the mask pattern can be formed on the upper surface of the block bar, and when applied to the manufacture of a monolithic magnetic head slider,
The accuracy of the track portion due to etching is improved, and the yield can be increased.

[0014]

EXAMPLE A resist coating process of the present invention is shown in FIGS. As shown in FIG. 1, a resist substrate (1) whose surface is formed as flat as possible is coated with a first resist (2), and the entire surface is exposed. Then, an air bearing is formed on the first resist (2). A second resist (3) required for forming the track portion and the track portion is applied. Since the resist substrate (1) has high plane accuracy,
The plane accuracy of the surfaces of the second resists (2) and (3) naturally increases.

On the other hand, as shown in FIG. 2, several block bars (5) and (5) are bonded to the work substrate (4) to be integrated into a wafer. This bond is a resist with low viscosity and good corrosion resistance.
(6) is used as an adhesive, and the resist (6) is permeated between the substrate (4) and the block bar group by the capillary action of the capillary.

Next, an adhesive resist (7) is applied to the upper surface of the block bar group, and the work substrate (4) is covered with the resist substrate (1) upside down as shown in FIG. On top of the adhesive resist (7) of 4), the second resist substrate (1)
The substrates (1) and (4) are fixed by closely contacting the resist (3).

After that, the substrates (1) and (4) are dipped in a developing solution. As shown in FIG. 4, the first resist (2) previously exposed.
Is dissolved in the developing solution, the work substrate (4) and the resist substrate (1) are separated, and the resist layer (3a) having high plane accuracy is formed on the upper surface of the block bar group on the work substrate (4). It is formed.

Next, as shown in FIG. 5, the resist layer (3a) on the block bar group is exposed to ultraviolet rays through a mask (8) in which a predetermined shape air bearing portion and track portion are drawn, Develop to expose the ferrite surface.

Only the exposed ferrite surface is etched to a predetermined depth by dry etching such as ion beam etching, and the work substrate (4) is removed from each block bar.
(5) is separated to obtain a block bar having an air bearing part (9) and a track part (50) as shown in FIG.

Next, the etched block bar is subjected to necessary processing such as outer diameter forming by cutting and slicing to complete a two-rail monolithic magnetic head slider as shown in FIG.

In the case of the MIG type two-rail monolithic type magnetic head slider in the embodiment, the resist used, the exposure conditions and the ion beam etching conditions are as follows. a. The first resist (2) has a viscosity of 400 cp and is spinner coated at 3000 rpm for 20 seconds to obtain a resist thickness of 7 μm. b. The second resist (3) has a viscosity of 800 cp and spinner coating is performed twice for 20 seconds at a rotation speed of 3000 rpm to obtain a resist thickness of 20 μm. c. The resist (6) for adhering the block bar (5) to the work substrate (4) and the resist (7) for fixing the work substrate (4) and the resist substrate (1) both have a viscosity. Two
It is 0c. d. The exposure conditions for patterning the second resist (3) are an ultraviolet illuminance of 12 mw / cm ² and an exposure time of 2 minutes and 30 seconds. e. The air bearing part (9) and the track part (50) are etched by ion beam etching, and the acceleration voltage is 700
V is etched at an etching angle of 30 ° to a depth of 10 μm.

The following points can be mentioned as effects of the present invention in the above embodiment. ． Even if there are slight steps or gaps in the block bar group adhered to the work substrate (4), the resist resist for coating on the block bar group absorbs them and the resist layer (3a ) Can be formed, and exposure can be realized by increasing the degree of adhesion with the mask. ． As a result, a uniform resist pattern can be formed on the upper surface of the block bar (5), and the track width accuracy after etching is significantly improved. ． Since the resist (3) can be applied thickly on the block bar (5) and the thickness of the resist can be controlled, ion beam etching can be performed, and the MIG type magnetic head slider is provided with a metallic magnetic material such as sendust. However, the track portion can be formed. ． Conventionally, if the upper surface of the resist (3) is uneven, the mask (8)
Although the resist may be damaged and the mask pattern may be contaminated at the time of contact with the mask, since the flatness of the upper surface of the resist is high, the resist is not damaged at the time of contact with the mask, and the mask pattern is not contaminated. ． Since the block bar (5) is integrated into a wafer with the resist (6) having good corrosion resistance, the blocks can be processed without separation during etching.

The present invention is not limited to the configuration of the above embodiment, and various modifications can be made within the scope of the claims.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a resist substrate coated with a resist.

FIG. 2 is a cross-sectional view of a state in which a block bar is joined to a work substrate.

FIG. 3 is a cross-sectional view of a state in which a work substrate and a resist substrate are joined.

FIG. 4 is a cross-sectional view of a state in which a resist substrate is separated from a work substrate.

FIG. 5 is a cross-sectional view of the block bar covered with a mask.

FIG. 6 is a perspective view of a block bar after etching is completed.

FIG. 7 is a perspective view of a two-rail monolithic magnetic head slider.

FIG. 8 is a perspective view of a block bar before etching.

FIG. 9 is a perspective view showing a state where a resist is applied to a block bar.

FIG. 10 is a perspective view showing a state where an etching pattern is formed on a block bar.

FIG. 11 is a cross-sectional view of a state in which a block bar is joined to a work substrate in a conventional example.

FIG. 12 is a sectional view showing a state in which a resist is applied to the block bar in the above.

FIG. 13 is a cross-sectional view showing a state in which the resist is covered with a mask in the above.

[Explanation of symbols]

 (1) Resist substrate (2) First resist (3) Second resist (4) Work substrate (5) Block bar

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[Procedure amendment]

[Submission date] June 11, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0015

[Correction method] Change

[Correction content]

On the other hand, as shown in FIG. 2, several block bars (5) and (5) are bonded to the work substrate (4) to be integrated into a wafer. This bond is a resist with low viscosity and good corrosion resistance.
(6) is used as an adhesive, and the resist (6) is permeated between the substrate (4) and the block bar group by a capillary phenomenon.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction content]

In the case of the MIG type two-rail monolithic type magnetic head slider in the embodiment, the resist used, the exposure conditions and the ion beam etching conditions are as follows. a. The first resist (2) has a viscosity of 400 cp and is spinner coated at 3000 rpm for 20 seconds to obtain a resist thickness of 7 μm. b. The second resist (3) has a viscosity of 800 cp and spinner coating is performed twice for 20 seconds at a rotation speed of 3000 rpm to obtain a resist thickness of 20 μm. c. The resist (6) for adhering the block bar (5) to the work substrate (4) and the resist (7) for fixing the work substrate (4) and the resist substrate (1) together have a viscosity of 20.
cp. d. The exposure conditions for patterning the second resist (3) are an ultraviolet illuminance of 12 mw / cm ² and an exposure time of 2 minutes and 30 seconds. e. The air bearing part (9) and the track part (50) are etched by ion beam etching, and the acceleration voltage is 700
V is etched at an etching angle of 30 ° to a depth of 10 μm.

[Procedure 3]

[Document name to be amended] Statement

[Name of item to be corrected] 0022

[Correction method] Change

[Correction content]

The following points can be mentioned as effects of the present invention in the above embodiment. ． Even if there are slight steps or gaps in the block bar group adhered to the work substrate (4), the resist resist for coating on the block bar group absorbs them and the resist layer (3a ) Can be formed, and exposure can be realized by increasing the degree of adhesion with the mask. ． As a result, a uniform resist pattern can be formed on the upper surface of the block bar 5, and the track width accuracy after etching is greatly improved. ． Since the resist (3) can be applied thickly on the block bar (5) and the thickness of the resist can be controlled, ion beam etching can be performed, and the MIG type magnetic head slider is provided with a metallic magnetic material such as sendust. However, the track portion can be formed. ． Conventionally, if the upper surface of the resist (3) is uneven, the mask (8)
Although the resist may be damaged at the time of contact with the mask pattern and the mask pattern may be contaminated, the resist is not damaged at the time of contact with the mask and the mask pattern is not contaminated because the plane accuracy of the upper surface of the resist is high. ． Since the block bar (5) is integrated into a wafer with the resist (6) having good corrosion resistance, the blocks can be processed without separation during etching.

Claims (1)

[Claims] 1. A first resist (2) is applied to a resist substrate (1) having a high level of plane accuracy, the resist is exposed over the entire surface, and a second resist (3) necessary for forming a fine pattern is formed as the first resist. (2) Ferrite block bar applied on top to form a fine pattern
A work such as (5) is fixed on the second resist (3), and then developed to dissolve only the pre-exposed first resist (2) in a developing solution, and the second resist ( Resist layer (3) with high plane accuracy
A method of applying a resist, which comprises forming a).